package com.atguigu.educenter.controller;

import com.atguigu.educenter.entity.UcenterMember;
import com.atguigu.educenter.service.IUcenterMemberService;
import com.atguigu.educenter.utils.ConstantWxUtils;
import com.atguigu.educenter.utils.HttpClientUtils;
import com.atguigu.servicebase.exceptionhandler.GuliException;
import com.atguigu.utils.JwtUtils;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.google.gson.Gson;
import io.jsonwebtoken.Jwt;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.HashMap;
import java.util.UUID;
import java.util.concurrent.TimeUnit;

/**
 * @create: 2022/10/8
 * @Description:
 * @FileName: WxApiApplication
 * @自定义内容：
 */
@Controller //只是请求地址，不需要返回数据
@RequestMapping("/api/ucenter/wx")
public class WxApiApplication {

    @Autowired
    private IUcenterMemberService iUcenterMemberService;

    @Autowired
    private RedisTemplate<String, String> redisTemplate;

    //2 获取扫描人信息，添加数据
    @GetMapping("callback")
    public String callback(String code, String state,HttpServletRequest httpServletRequest) {
        try {
            //1 获取code值，临时票据，类似于验证码
            //得到授权临时票据code


            //从redis中将state获取出来，和当前传入的state作比较
            //如果一致则放行，如果不一致则抛出异常：非法访问
            String redisGetState = redisTemplate.opsForValue().get("wechar-open-state-" + httpServletRequest.getSession().getId());
            if (!redisGetState.equals(state)){
                throw new GuliException(20001,"非法访问!");
            }

            //2 拿着code请求 微信固定的地址，得到两个值，access_token和 openid
            //向认证服务器发送请求换取access_token
            String baseAccessTokenUrl = "https://api.weixin.qq.com/sns/oauth2/access_token" +
                    "?appid=%s" +
                    "&secret=%s" +
                    "&code=%s" +
                    "&grant_type=authorization_code";

            //拼接三个参数：id、密钥和code值

            String accessTokenUrl = String.format(
                    baseAccessTokenUrl,
                    ConstantWxUtils.WX_OPEN_APP_ID,
                    ConstantWxUtils.WX_OPEN_APP_SECRET,
                    code
            );

            //请求这个拼接好的地址，得到两个值，access_token和 openid
            //使用httpClient发送请求，得到返回结果
            String accessTokenInfo = HttpClientUtils.get(accessTokenUrl);

            //从accessTokenInfo字符串获取出来两个值 access_token 和 openid
            //把accessTokenInfo字符串转换map集合，根据map里面key获取对应值
            //使用json转换工具 Gson
            Gson gson = new Gson();
            HashMap mapAccessToken = gson.fromJson(accessTokenInfo, HashMap.class);
            String access_token = (String) mapAccessToken.get("access_token");
            String openid = (String) mapAccessToken.get("openid");


            //把扫描人信息添加数据库里面
            //判断数据表里面是否存在相同微信信息，根据openid判断
            UcenterMember member = iUcenterMemberService.getOpenIdMember(openid);

            if (member == null) { //member是空，表没有相同微信数据，进行添加


                // 3拿着的到access_token 和 openid，再去请求微信提供固定的地址，获取到扫描人信息
                // 访问微信的资源服务器，获取用户信息
                String baseUserInfoUrl = "https://api.weixin.qq.com/sns/userinfo" +
                        "?access_token=%s" +
                        "&openid=%s";
                String userInfoUrl = String.format(
                        baseUserInfoUrl,
                        access_token,
                        openid
                );

                //发送请求
                String userInfo = HttpClientUtils.get(userInfoUrl);

                //获取返回userInfo字符串扫描人信息
                HashMap mapUserInfo = gson.fromJson(userInfo, HashMap.class);
                String nickname = (String) mapUserInfo.get("nickname");
                String headimgurl = (String) mapUserInfo.get("headimgurl");


                member = new UcenterMember();
                member.setOpenid(openid);
                member.setNickname(nickname);
                member.setAvatar(headimgurl);
                iUcenterMemberService.save(member);
                QueryWrapper<UcenterMember> wrapper = new QueryWrapper<>();
                wrapper.eq("openid", openid);
                UcenterMember one = iUcenterMemberService.getOne(wrapper);

                if (one.getIsDisabled()) {
                    throw new GuliException(20001, "您的账号也被禁用！");
                }
            }

            //使用jwt根据member对象生成token字符串
            String jwtToken = JwtUtils.getJwtToken(member.getId(), member.getNickname());
            //最后：返回首页面，通过路径传递token字符串
            return "redirect:http://localhost:3000?token=" + jwtToken;
        } catch (Exception e) {
            e.printStackTrace();
            throw new GuliException(20001, "登录失败！");
        }
    }

    //1 生成微信扫描二维码
    @GetMapping("genQrConnect")
    public String genQrConnect(HttpSession session, HttpServletRequest httpServletRequest) {
//        //固定地址，后面拼接参数
//        String url = "https://open.weixin.qq.com/connect/qrconnect";

        // 微信开放平台授权baseUrl %s相当于?代表占位符
        String baseUrl = "https://open.weixin.qq.com/connect/qrconnect" +
                "?appid=%s" +
                "&redirect_uri=%s" +
                "&response_type=code" +
                "&scope=snsapi_login" +
                "&state=%s" +
                "#wechat_redirect";

        //对redirect_url进行URLEncoder编码
        String redirectUrl = ConstantWxUtils.WX_OPEN_APP_REDIRECT_URL;
        try {
            redirectUrl = URLEncoder.encode(redirectUrl, "utf-8");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }

        // 防止csrf攻击（跨站请求伪造攻击）
        String state = UUID.randomUUID().toString().replaceAll("-", "");//一般情况下会使用一个随机数
//        String state = "imhelen";//为了让大家能够使用我搭建的外网的微信回调跳转服务器，这里填写你在ngrok的前置域名
//        System.out.println("state = " + state);

        // 采用redis等进行缓存state 使用sessionId为key 30分钟后过期，可配置
        //键："wechar-open-state-" + httpServletRequest.getSession().getId()
        //值：state
        //过期时间：30分钟
        redisTemplate.opsForValue().set(
                "wechar-open-state-" + httpServletRequest.getSession().getId(),
                state,
                30,
                TimeUnit.MINUTES
        );

        //设置%s里面的值
        String url = String.format(
                baseUrl,
                ConstantWxUtils.WX_OPEN_APP_ID,
                redirectUrl,
                state
        );
        return "redirect:" + url;
    }
}
